Metal-sawing machine



{No Model.) 3 Sheets-Sheet 1.

J. F. LUNDAHL. METAL SAWING MAGHINE.

No. 518,572. I Patented Apr. 17, 189 4.

(No Model.) 3 Sheets-Sheet 2.

J. P. LUNDAHL.

METAL SAWING MACHINE. No. 518,572. Patented Apr. 17, 1894.

(No Model.) 4 3 SheetsSheet 3. J. F. LUNDAHL. METAL SAWING MAGHINE. No. 518,572. Patented Apr. 17, 1894.

WASHINGTON. a, n4

me NAYIONAL LITKOGRAPHING coMPANv.

I v I llNrTno STATES PATENT Fries.

J OHAN FRITHlOF LUNDAHL, OF HOMESTEAD, PENNSYLVANIA.

M ETAL-SAWI NG MACH l N E.

SPECIFICATION forming part of Letters Patent No. 518,572, dated April 1'7, 1894.

Application filed June 30, 1892. Serial No. 438,544. (No model.)

T0 at whom it may concern.-

Be it known that I, J OHAN FRIrHIoF LUN- DAHL, of Homestead, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Metal-Sawin g Apparatus, of which the followlng 1s a full, clear, and exact description, reference being had to the accompanying draw posts 2, connected by a cap or entablature 3,

and having a suitably secured base-plate 4- The saw-holder consists of a lever or frame 5 pivotally mounted at its rear end 6 in bearings on a standard 7, and extending between and beyond the posts of the housing,betwecn which posts it has abearing and is vertically movable radially on its axis. Such vertical radial motion is effected by means of a mo tor set in the entablature 3 and comprising a hydraulic cylinder 8 and a plunger 9, the movable part of the motor (in this case the plunger) having a bearing upon the saw holder. By projecting the plunger of this cylinder, the saw-holder and saw are moved vertically downward. To raise them I employ a counterbalance consisting preferably of a cylinder 10 which is set in the base of the machine and has a plunger 11, also bearmg on the saw holder. There is preferably a constant communication between the counterbalancing cylinder 10 and the accumulator or source of water pressure, so that a continual upward pressure is exerted on the sawholder, and the cross-section of the cylinder is of sufficient area, relatively to the cylinder 8, that, when the latter is disconnected from the source of supply, the counterbalancing cylinder shall raise the saw-holder and displace the water from the cylinder 8, but that when the supply valve of the cylinder 8 is opened the saw-holder shall be forced down against the pressure of the counterbalancing cylinder.

In order to accommodate the slight relative lateral motion between the saw-holder and the plungers of the cylinders, caused by the pivoting of the holder, I interpose rollers 12 between the plungcrs and the holder, providing the latter with retaining cavities or boxes and fitting the plungers and holder with hard steel plates 13, against which the rollers immediately bear and which serve to prevent injurious wear. The saw 14 is fixed toashaft or arbor 15, jourualed in bearings 16 at the end of the saw-holder, and provided with a belt-pulley 17, which extends back to amaiu driving pulley and derives its power therefrom. The posts 2 are situated between the saw and the pivot of the saw-holding lever, and therefore serve as a bearing for said lever at an intermediate portion of its length.

In using the apparatus, the metal piece to be sawed is placed beneath the saw and then by operating the cylinder, as above described, the saw-holder is depressed so as to force the saw down upon the metal, and the saw being driven by the belt mechanism performs the work of cutting.

The advantages of my invention will be appreciated by those skilled in the art.

The apparatus is strong, durable and cheap, and by reason of the pivotal arrangement of the saw-holder the transmission of power to it is simplified, and the use of the housings which bear upon the pivoted saw-holder at a point between the pivot and the saw steadies the holder and prevents lateral deflection motor by which said lever is moved on its pivot and the saw is forced against the metal piece to be cut; said posts being situated between the position of the saw and the pivot of the lever; substantially as described.

2. In metal-sawing apparatus, the combination of a pivotally movable saw-holding lecomprising a cylinder and plunger acting on ver, posts between whichitis set and by which the lever to force the saw into the metal piece it is guided and supported laterally, a motor to be cut, and a roller interposed between the comprising a cylinder and plunger, acting on lever and the movable part of the motor; sub- I 5 5 the lever in one direction, and-a counterbalstantially as described.

ance acting thereon in the opposite direction; In testimony whereof I have hereunto set substantially as described. my hand this 28th day of June, A. D. 1892. 3. In metal-sawing apparatus, the combi- J OHAN FRITH'IOF LUNDAHL. nation of a pivotally movable saw-holding le- 7 Witnesses: LO ver, posts between which it is set and by which DAVID LAING,

it is guided and supported laterally, a motor W. H. CORBETT.' 

